As an audio communication system for performing an audio conference (conference call) in a remote location, an audio conference device integrally including a speaker and a microphone has been released. The audio conference device transmits a sound signal collected by the microphone to a connection destination and emits a sound signal, received from the connection destination, from the speaker. When the conference is held by a plurality of persons, such an audio conference device is usually installed in the center of conference participants (the center of a conference desk or the like). Therefore, it is desirable to miniaturize this audio conference device, and for example, an audio conference device miniaturized by omitting a speaker box as shown in Patent Document 1 has been proposed.
When a sound signal received from the connection destination is emitted from the speaker since the audio conference device is configured to have the speaker and the microphone within the same space, such a sound is collected as an echo to the microphone and a collected sound signal including the echo is transmitted to the connection destination. In an audio conference device having an echo canceller function as shown in Patent Document 2, an audio conference device for accommodating the microphone at the tip end of a tube-shaped elastic body and suppressing acoustic coupling between the speaker and the microphone has been proposed.
However, in the configuration of Patent Document 1, a compact configuration is provided, but the speaker and the microphone are close to each other and the amount of wraparound sound from the speaker to the microphone is large. On the other hand, in the configuration of Patent Document 2, the wraparound sound is suppressed by the echo canceller function and the acoustic coupling inside the case is suppressed by the elastic body, but the speaker and the microphone are still close to each other for a compact configuration as in Patent Document 1. For this reason, there is still a problem in that a sound emitted from the speaker is apt to wrap around the microphone and a heavy processing burden is imposed on the echo canceller function.
An object of the present invention is to provide a sound emission and collection device having a compact configuration and being capable of suppressing a wraparound sound from a speaker to a microphone and improving an S/N ratio.
[Patent Document 1] Japanese Patent Application, First Publication No. 8-204803.
[Patent Document 2] Japanese Patent Application, First Publication No. 8-298696